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Admin
Forum Admin

USA
635 Posts

Posted - 06/19/2012 :  21:45:18  Show Profile  Reply with Quote
What result do you get? I get 13, but my son insists it is 4.

16-6x22(5-3)

Thanks,
Gisele
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royhaas
Moderator

USA
3059 Posts

Posted - 06/20/2012 :  09:50:03  Show Profile  Reply with Quote
16-622(5-3)=16-622(2)=16-624=16-124=16-3=13.
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Admin
Forum Admin

USA
635 Posts

Posted - 06/20/2012 :  10:17:05  Show Profile  Reply with Quote
quote:
Originally posted by royhaas

16-622(5-3)=16-622(2)=16-624=16-124=16-3=13.




Thanks Roy. My thoughts exactly. This question will be included in an upcoming Flash game.
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Ultraglide
Advanced Member

Canada
299 Posts

Posted - 06/25/2012 :  12:40:35  Show Profile  Reply with Quote
Looking at part of the question, i.e. 6x22(2), this is the same as 6x22x2. Now if we follow the order of operations - multiplication and division in order from left to right this gives 12. So the final answer is 4.
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Admin
Forum Admin

USA
635 Posts

Posted - 06/25/2012 :  15:53:14  Show Profile  Reply with Quote
quote:
Originally posted by Ultraglide

Looking at part of the question, i.e. 6x22(2), this is the same as 6x22x2. Now if we follow the order of operations - multiplication and division in order from left to right this gives 12. So the final answer is 4.



Thank you for your input, UltraGlide. I guess if us math folk can't agree on the solution, then this is not a good problem to hard code into a Flash game. I will post it on Facebook, though.

Gisele
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Ultraglide
Advanced Member

Canada
299 Posts

Posted - 06/25/2012 :  17:02:22  Show Profile  Reply with Quote
If you want to answer to come out to 13, just put parentheses around the 2(2) i.e. [2(2)].
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the_hill1962
Advanced Member

USA
1468 Posts

Posted - 06/26/2012 :  15:54:23  Show Profile  Reply with Quote
I agree that the answer is 4.
This is the reason why I have never liked the
"Please Excuse My Dear Aunt Sally" (or PEMDAS) acronym.
They do come to me knowing the acronym PEMDAS though so I suppose it served its purpose (having them remember the order).
I tell them since multiplication and division are at the same level, so that PEMDAS is misleading if you forget that detail.
This topic provides an example.
I write on the board PEmdAS.
I hook together the md and the AS (sort like they do in company logos hooking together letters).

Edited by - the_hill1962 on 09/13/2012 12:47:48
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royhaas
Moderator

USA
3059 Posts

Posted - 06/27/2012 :  11:32:08  Show Profile  Reply with Quote
If you faithfully follow the PEMDAS precedence rules, then the answer on almost any calculator is 4,

16-6*2/2*(5-3)=16-6*2/2*2=16-6*2/2*2=16-(6*2/2*2)=16-12=4.

Multiplication and division have the same precedence, so the (re-)grouping is allowed. It seems that this is a common problem when both multiplication and division are concerned. That's why I trust my calculator more than my hand arithmetic.

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Admin
Forum Admin

USA
635 Posts

Posted - 06/27/2012 :  11:38:58  Show Profile  Reply with Quote
Thanks everyone for your input!

Gisele
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